Hermaphroditic multi-contact reed switch



Oct. 7, 1969 R. E. NEUBER HERMAPHRODITIC MULTI-CONTACT REED swITcn Filed March 14, 196e 2 Sheets-Sheet 1 INVENTOR. RALPH E. Nausea ATTORNEY OC- 7, 1959 R. EQNEUBER 3,471,813

HERMAPHRODITIC MULTI'CONTACT REED SWITCH Filed March 14. 1968 2 Sheets-Sheet FORM A PAIR oF SIMILAR HEADERS l INcLuDING AN msuLA'roIz AND swIrcII McMBeRs cIRcuMI-'fRENI-IALLY Roure om: HEADER wIrII RESPECT To THE OTHER Ammer/CALM l:SEAL Menaces VIN OPPOSITE EN oF TuBuLAR Nvt-Lope y INVENTOR.

RALPH E. Neuem BY AJ ya ATTORNEY United States Patent O U.S. Cl. 335-152 6 Claims ABSTRACT or THE DISCLOSURE A hermaphroditic multi-contact reed switch includes a tubular envelope having a pair of substantially identical headers sealed into the opposite ends and contains an inert atmosphere. Each of the headers includes a plurality of switch members having a magnetizable portion extending interiorly of the envelope and in longitudinally overlapping relationship with the magnetizable portion of the switch members of the opposite header. The longitudina-l overlapping magnetizable portions of the matching switch members of the opposing headers have a desired gap therebetween whidh is dependent upon the circumferential displacement of one header with respect to the other.

BACKGROUND OF THE INVENTION The prior art suggests numerous so-called reed switches wherein a pair of magnetizable contact members are disposed in overlapping spaced relationship within an envelope and activated by application of controllable magnetic field. Also, the prior art suggests numerous similar devices wherein a number of such contacting members are included within the same envelope.

Although many of the above-mentioned devices have provided excellent service in numerous applications, it (has been found that there are certain applications wherein the known structure leave something to be desired. More specifically, it has been found that known reed switch structures usually include switch members sealed into the ends of the envelope which tends to provide a nonuniform Iseal and a non-uniform spacing intermediate the magnetizable switch members. Also, such sealing techniques wherein glass-to-metal seals, `for example, are employed require delicate controls to prevent oxidation of the metal switch members. Moreover, all of the switch members of the known multiple-contact devices are not concentric with respect to the envelope and to the energizing means `surrounding the envelope which tends to cause a non-uniform magnetic eld intensity insofar as a multiple-contact device is concerned.

OBJECTS AND SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide an improved hermaphroditic multi-contact reed switch. Another object of the invention is to provide an improved process for fabricating hermaphroditic multicontact reed switches. Still another object of the invention is to enhance the uniformity of operation of a hermaphroditic multi-contact reed switch. A further object lof the invention is to improve the hermetic sealing and reference level of the contacts within a hermaphroditic multicontact reed switch. A still further object of the invention is to provide an enhanced supporting structure for the contacts of a hermaphroditic multi-contact reed switch.

These and other objects and advantages are achieved in one aspect of the invention by a hermaphroditic multicontact reed switch having a pair of substantially identical headers each including an insulator support and a plurality of switch members embedded therein and extending therethrough. '[ihe headers are circumferentially displaced PAce with respect to one another and sealed into opposite ends of a tubular envelope to provide a spaced longitudinal overlapping of the switch members which are activated by a magnetic field developing means surrounding the envelope.

The hermaphroditic multi-contact reed switch is constructed by a process which includes fabricating a pair of substantially identical headers, circumferentially rotating the headers with respect to one another, and hermetically sealing the headers into opposite ends of a tubular envelope.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a preferred embodiment of a hermaphroditic multi-contact reed switch;

FIG. 2 is a plan view of the embodiment of FIG. 1;

FIGS. 3, 4 and 5 are embodiments lof headers suitable for the embodiment of FIG. l; and

FIG. 6 is a flow chart of the construction of the hermaphroditic multi-contact reed switch.

DESCRIPTION OF THE PREFERRED EMBODIMENT For a better understanding of the present invention, together with other and further objects, advantages and capabilities thereof, reference is made to the following disclosure and accompanying drawings.

Referring to the drawings, FIG. 1 illustrates a hermaphroditic four-contact reed switch. The switch includes a tubular envelope 7 of a material such as glass and has a pair of opposite ends 9 and 11. A pair of substantially similar headers, 13 and 1S are hermetically sealed into the opposite ends 9 and 11 of the envelope 7.

The headers 13 and 15 each include an insulator support 17 such as glass, wherein a plurality of switch members 19 are embedded. The switch members 19 each include a magnetizable portion 21 which is flexible and of a material such as iron or a nickel-iron alloy and extends interiorly of the envelope 7. Also, each of the switch members 19 includes a connector portion 23 extending exteriorly of the envelope 7 to provide an electrical connecting means.

Further, the longitudinal axis of each of the magnetizable portions 21 is displaced from the longitudinal axis of the connector portions 23 in a direction substantially normal to these longitudinal axes. Also, the displacement of each of the magnetizable portions 21 from the longitudinal axis of the connector portion 23 is substantially one-half the total desired gap 25 or distance intermediate a pair of magnetizable portions 21.

In this particular embodiment, the four switch members 19 are spaced in quadrature as illustrated in the plan view of FIG. 2. Tlhese quadrature spacedswitch members 19 form two diametrically opposing pairs with the magnetizable portions 21 of one pair formed such that the diametric distance X between the longitudinal axes thereof is greater than the diametric distance Y between the longitudinal axes of the connector portions 23. The other pair is formed in an opposite fashion in that the diametric distance A between the longitudinal axes of the magnetizable portions 21 is less than the diametric distance B between the longitudinal axes of the connector portions 23.

As mentioned above, the headers 13 and 15 are hermetically sealed to opposite ends 9 and 11 of the envelope 7, and provide a longitudinal overlapping of the magnetizable portion 21 of the switch members 19 extending interiorly of the envelope 7 from each of the headers 13 and 15. Also, the yheaders 13 and 15 are in circumferentially displaced relationship with respect to one another to provide a desired gap 25 or distance intermediate each pair of ylongitudinally overlapping magnetizable portions 21. In this particular instance, the circumferential relationship is a quadrature relationship although it is obvious that other switch member forms and circumferential relationships are applicable and appropriate.

The pairs of magnetizable portions 21 forming each one of the gaps 25 are equi-distantly spaced from the circumference of the tubular envelope 7 and a magnetic eld developing means 27 such as an electromagnet for instance, surrounds the tubular envelope 7. Thus, each pair of magnetizable portions 21 of the switch members 19 is equiedistantly spaced from the magnetic eld developing means 27 and subjected to substantially the sarne magnetic eld intensity.

Referring back to the headers 13 and 15, FIGS. 2, 3, and 4 illustrate several suitable embodiments. In FIG. 3, a plurality of switch members 29 are embedded in and pass through an insulator 31 such as glass. Each of the switch members 29 has magnetizable portion 33 and a connector portion 35 which extend outwardly in opposite directions from the insulator 31. Also, the magnetizable portion 33, which is both magnetic and iiexible, is formed such that the insulator 31 serves as a rigid and uniform base wherein the cantilevered magnetizable portion 33 bends.

FIG. 4 is a structure somewhat similar to FIG. 2. Herein, each of the switch members 29 ihas beads 37 of the same material as the insulator 31 bonded to the insulator 31 and surrounding, supporting and sealed to both the magnetizable and connector portions 33 and 35 respectively. Also, a tubular exhaust stem 39 is aiiixed to the insulator 31 in a manner well known in the art lo provide a means for replacing the atmosphere of the device with desired inert atmosphere.

Also, FIG. illustrates a plurality of switch members 29 sealed into and passing through an insulator 31 and a button 41 bonded thereto. In this instance, the button 41 not only enhances the rigidity and sealing of the switch members 29 but also serves to protect the seal intermediate the switch members 29 and insulator 31 from thermal shock upon application of heat, soldering for instance, to the switch members 29.

As to the construction of a hermaphroditic multi-contact reed switch, reference is made to the flow chart of` FIG. 6. Therein, a plurality of similar headers are fabricated by sealing a plurality of switch members including magnetizable and connector portions into an insulator. Obviously, the switch members are preferably of the preformed variety but may be formed after embodiment in the insulator. Also, the formed switch members are readily adapted to both spacing adjustment and cleaning after having been sealed into the insulator.

Then, a pair of the headers are circumferentially rotated with respect to one another to provide a desired gap intermediate associated pairs of magnetizable portions. This pair of headers is hermetically sealed to opposite ends of a tubular envelope which, in the preferred embodiment, involves a glass-to-glass sealing technique and a relatively small distortion of the envelope to provide contact thereof with the headers. Moreover, the atmosphere within the envelope may then be replaced by a dry inert atmosphere utilizing an exhaust tube in a manner well-known in the art.

Thus, there has been provided a unique hermaphroditic multi-contact reed switch having numerous advantages over other known reed switches. The multi-contact switch is volumetrically eicient as compared with single-contact devices providing a consequent reduction in cost per contact. Also, the header-type construction lends itself to the formation of a rigid and uniform support whereon the `flexible magnetizable portion of the switch members is dependent. Further, the header-type construction provides individual sealing of the switch members to the headers and hermetic sealing of the headers to the envelope which not only permits cleaning and adjustment of the switch members but also a relatively small distortion of the envelope wherein the headers are hermetically sealed.

Additionally, the header-type construction facilitatesl circumferential displacement of the headers with respect to one another prior to sealing and enhances compensation for distortion of the switch members due to handling and transfer during fabrication.

Moreover, the hermaphroditic form of the headertype construction is economical of apparatus, time, and inventory of parts.

While there has been shown and described what is at present considered the preferred embodiments of the invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention as defined by the appended claims.

What is claimed is:

1. A hermaphroditic multi-contact reed switch comprising in combination:

a substantially tubular envelope having a longitudinal axis and a pair of opposing ends;

a pair of substantially identical headers in circumferential displaced spaced relationship with respect to one another hermetically sealing said opposing ends of said envelope, each of said headers including an insulator and a plurality of switch members embedded therein and extending therethrough, said switch members each having a magnetizable portion extending interiorly of said envelope and a connector portion extending exteriorly of said envelope with said magnetizable portion of each of said switch members of one header in longitudinal overlapping spaced relationship with the magnetizable portion of said switch members of said other header; and

a magnetic field developing means surrounding said envelope and uniformly spaced from said overlapping magnetizable portions of said switch members.

2. The hermaphroditic multi-contact reed switch of claim 1 wherein said envelope contains an inert atmosphere.

3. The hermaphroditic multi-contact reed switch of claim 1 wherein each of said pair of headers includes beads bonded thereto and substantially surrounding a part of each switch member.

4. The hermaphroditic multi-contact reed switch of claim 1 wherein each of said pair of headers includes a button member bonded thereto and substantially surrounding a part of all of said switch members embedded in said header.

5. The hermaphroditic multi-contact reed switch of claim 1 wherein said magnetizable portion and said connector portion of each of said switch members each have a longitudinal axis displaced from one another in a direction normal to said longitudinal axes.

6. The hermaphroditic multi-contact reed switch of claim 1 wherein each of said pair of headers includes four switch members embedded therein, said switch members are arrayed in quadrature relationship to form two pairs of switch members, each of said pairs of switch members having a different radial spacing from the envelope circumference than the other and said headers having a quadrature relationship with respect to one another.

References Cited UNITED STATES PATENTS 3,114,018 12/1963 Koda et al. 335-152 FOREIGN PATENTS 1,021,233 3/ 1966 Great Britain.

BERNARD A. GILHEANY, IPrimary Examiner R. N. ENVALL, J R., Assistant Examiner U.S. C1. X.R. zoe-166 

